Improvement in iroh bridges



4diagonals or ties of' an iron :bridge to the. chords ofthe bril ge;and,

. block, and require no further aid to retain them, the' A boing en tlreupper dell' lter-tea Leners Parent No. 104,902, dazed .noie 2e, 18m

. IMPROVEMENT IN IRON BRIDGE The Schedule referred to in these LettersPatent and making part o! the saine.

Be it known that I, Looms E. TRUESDELL, of'. Warren,l in the county ofWorcester and State of' Massachusetts, have invented certainImprovements' in Iron Bridges, of which the following is a full, clear,and exact description, reference being had 'to the accompanying drawingmakingr part of' this specification, in which- .Y v

Figure 1 represents aside elevation of the improved bridge, and l-liigures 2, 3, and 4, a side elevation of the blocks to which mypresent irnprovenrerrt is more immediately confined, a portion of their'side being removed Ato illustrate the peculiar' construction of theconnection, lig. being the top block and iig. 3 the lower-block.

Figure represents a plan of the bottom block, and

Figure 6 an end view ofthe same. v

Figure 7 represents a top riew of the top block, and

Figure 8 a section of the top chor'd. f

Figure 9 represents the post foreslrortencd by breaking, and l l Figure10 a eross-secrron oiV its bottoni. .Figure 11, a key sometimes used forthe purpose oftightening the-top chord. I.

y .Figure 12 represents vthe s plieing'ol` the eudsof two of the lowerchords with the clamps that confine them, and

Figure 13 a plan oi' the inside of one of the clamps, and v' Myinvention relates- First, to a new and improved 14 the metallic handthat y confines the :node of fastening the Secondly, to a new andimproved inode vof securing the ends ofthe lower chords to each other'.

The first, part of the invention consists- First, in corrugating eachend oi' the ties or (hago-- nais a. A

4Sec'oridl), in forming a corresponding counter-cor;v rugated key-wedgein two parts, c and c', so as to embrace the corrugated end ot' the tiesa?, the-outer sides of the double ley c and c' being made of a'wedge-shaped form, so that, when drawn down into a wedge-shaped openingformed'in the upper and lower block for its reception, and driven boinc,the end 0f the ties will in this' "way become firmly wedged in the 'formthe lower chord,

' the manner described;

operation being the same in both, with this exception, thai, infastening the tie to the upper block, the diagonal d is passedlhroughthe block A from its under side, and the key-blocks c and c' then4fitted over its corrugated endand the whole then' drawn down und drivenhome tightly in the block, the large end'ofthe edge-shaped opening inthe upper block side for this purpose,'while the reverse is true of thelower block, the lower end of the tie a. being' passed through from theupper side of the lower block, 'and then litted with the key, and drawnup into the bloeit, and forced home as the one above. A.

By this means, it will be apparent that the tie can never be withdrawnfrom either, unless great violence should be used either in forcing theupper chord down or the lower one up, a condition which cannot ariseunder ordinary circumstances. But, as tberevnray 'oe danger ol' burstingthe blocks A, either when driving the ties and their wedges home, orunder severe and sudden strains on the bridgethe blocks being made ofcast-iron- I slrrink,'for the purpose of preventing such a casualty, astrongr wrought-iron band, H, figs. 4, 5, and 6, around the blocks,which is amply snliicient for the purpose.

- The next part of my invention consists in splicing the ends of theparts-of the chord together, which by a corresponding eorrngation ontheend of each, s o as the corrugation of the one shall fit into thatof-the other, as represented iu iig. 12, in which position theyareembraced 4by two corrugated clamps, d and d', as shown in saidr'gure,and va plan ot' the inside of one of which is shown in lig. 13.

Previous to their being placed together', a band, s, iig. 14, is ir'rstslipped over the, end of one of the chords, when the two ends arebronghttogether, and the clamps put in place, and the band s, fig. 14,(it having first been heated for this purpose,) shrunk upon it, therebyforming a connection of the strongest and most enduring character. l

It will be apparent that any number of' parallel chords may be thusspliced together by one band, each chord, however, having its own. setof clamps.

Having thus describedmy iw'ention,

What I claim as new, and desire te secure by Letters Patent, is-

. 1.V Fastening the end of -thc tie a of an iron bridge fto the block A,either of the upper' or lower chord, in

that is tosay, by corrugating its 'end andnsing, in connectiontherewith, wedgeslraped corrugated-keys c and c', which arc made to,take into a corresporrdingly-sbaped opening in the block A, asdescribed, for the purposes set forth.

2. The combination oi' the wrought-iron band H with the block forth. A

3. The combination of the band s,ig.14, and clamps d and d', with thecorrugated ends ot' the "chords, for the purposes set forth. 1

` L. E. TRUESDELL.

Witnesses:

n l. HAXNAY,

Guo. liasses'.

A, as described; for the purposes set

